1. Technical Field
This invention relates to image development in electrostatographic copiers or printers, and more particularly to improvements in methods of and apparatus for replenishing toner in electrostatographic development stations.
2. Prior Art
Electrophotographic copiers and printers utilize toner particles dispensed from a development station to develop latent electrostatic images on image-bearing members such as, for example, photoconductors. The quantity of toner particles is gradually depleted through use and must be replenished periodically.
Replenishing toner particles can be an inefficient, messy, and expensive procedure due to the nature of toner particles, which usually consist of very fine thermoplastic particles pigmented with carbon black or coloring pigments. These particles are susceptible to forming powder clouds if blown or aerated. Blowing or aeration can easily result when handling toner containers, which are usually flexible so that the particles are aerated when the containers are squeezed. Not only are toner clouds messy, they can also cause maintenance problems for other components of the copier or printer if toner is deposited on sensitive components of the machine.
The patent literature includes a number of patents directed to the concept of a toner container having a flexible cover overlain by a slide cover received on a flange flush with the mouth of the container. Exemplary of such patents are U.S. Pat. Nos. 4,062,385; 4,573,614; 4,589,579; and 4,491,161. None of these patents discloses an arrangement for opening the containers to empty their contents and thereafter effectively resealing the empty containers with the flexible covers, wherein both operations are accomplished by sliding the containers on the electrostatographic development stations with which the containers are used.
In view of the limitations of the prior art, there is a need for improved arrangements for emptying toner containers closed with flexible covers wherein the containers are automatically resealed with the same flexible covers.